The centre of this talk was obviously the pituitary gland and the way tumours associated with it affect the body. I learned that the pituitary gland is made of two sections with separate functions; the anterior and the posterior. A hormone produced in the anterior called prolactin is associated with the production of milk in mammals and also 'switches off' the menstrual cycle during this process to prevent further reproduction. Without considering this factor, the West decided to send bottled milk to Africa for children to be fed with rather than breast milk from mothers, which meant they no longer required milk which halted prolactin production and restarted the menstrual cycle. This effectively reversed mother nature's contraception and caused a population surge. This is a good example of when meddling with nature can have unexpected consequences, something which should always be considered in medicine. The posterior of the pituitary gland is associated with the production of ADH and oxytocin, but the main disorders discussed related to the anterior.
The presentation of pituitary tumours seemed to be fairly generic at first, but could be anything from excess/deficiency in hormones to apoplexy in acute cases. They can also cause bitemporal hemianopia; a change in the field of vision due to pressure on the optic nerve or chiasm. Depending on where the gland is altered, there are varying physical effects.
One disorder is acromegaly, which is an excess of growth hormones, caused by hypopituitarism. An example used by the lecturer was a man called Gary Tiplady who was 7ft3! Because these tumours are so slow growing, the tumours are often not noticed for years, by which time the patient often has many other problems related to pituitary adenomas. This includes Cushing's diseases, caused by an excess in secretion of ACTH and production of steroids by the adrenals glands and can result in conditions such as diabetes, osteoporosis and obesity if not recognised and treated. Another condition could be Addison's (which JFK had) which is often known as tuberculosis of the adrenal glands and presents as increased pigmentation and often also vitiligo, which contrasts massively on the skin. People may have an Addisonian crisis if they have a lack of steroids which is why people who take steroid medication will carry a card around with them stating this.
We also looked at the thyroid as an area where problems often arise, thinking about both hypothyroidism and thyrotoxicosis. Hypothyroidism is often caused by an iron deficiency, but this cause is uncommon in the UK due to a good supply of iron in the diet. Thyrotoxicosis, however, is the opposite and can result in conditions such as Grave's disease, which is sometimes known as thyroid eye disease due to an antibody causing inflammation of the eye, meaning the patient often sees double. Grave's disease can also cause atrial fibrillation due to the overactive thyroid and this was exhibited in George Bush senior, when he collapsed on a golf course while in office as president as a symptom of his condition. This can be treated with inhibition of hormone synthesis orally or in extreme case with thyroid surgery. Alternatively, and more commonly in more current medicine, it can be treated with radioiodine, which is taken by the patient and ablates the thyroid. The patient is then given hormone replacement therapy to maintain the correct hormone balance usually controlled by the thyroid.
In the most extreme cases, hormone deficiency can cause pituitary apoplexy, which can present as a subarachnoid haemorrhage, with symptoms such as a severe headache and visual loss. It is vital in these cases that the hormones are replaced as quickly as possible otherwise it is potentially fatal.
Overall, the talk outlined to me that there are so many things that can go wrong with hormones in the body and it is so important that doctors are able to spot these disorders and treat them effectively. I was fascinated by the variety of conditions and the biochemistry that causes them. I continue to be amazed by the complexity of the human body, where there are so many opportunities for things to go wrong, yet the majority of us are lucky enough to be unaffected by these conditions. It seems almost unfair that most of us go through our lives completely blissfully unaware that these conditions exist and it's purely down to our genes and luck that we are not directly affected by them. It is in these situations where the vigilance and care of doctors, nurses and other medical professionals really come into their own and are able to provide life changing care and treatment.
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